Surface coverings, especially PVC-based surface coverings, are widely used to decorate buildings or houses surfaces as they are more pleasant, more aesthetic and more comfortable than a surface just painted.
However due to environmental issues on PVC coverings regarding VOC (Volatile Organic Compounds) release, plasticizers and thermal stabilizers toxicity, efforts on PVC alternatives were developed.
Rubber based or linoleum based surface coverings are PVC alternatives. However, such covering present the drawback of having an unpleasant odour and a lower mechanical resistance, or flexibility, as a PVC surface covering. Furthermore, Rubber or linoleum based surface coverings are not able to be processed on standard equipment used to process PVC surface coverings.
To respond to environmental constraints, it has been suggested, as described in WO 2008/042387, to replace the plasticizers by a high molecular weight thermoplastic polyester resin or a highly viscous polyester resin. It has also been suggested, to replace the PVC resin by acid modified polymers, as described in U.S. Pat. No. 7,175,904, in which the flooring substrate has a PVC-free composition comprising a terpolymer and a copolymer, the terpolymer comprising ethylene, methyl acrylate and acrylic acid, and the copolymer comprising ethylene and methacrylic acid.
However, a composition comprising acid modified polymers and a significant amount of fillers, 75 to 85% for example, is difficult to be calendered into a thin sheet, and the extractability of the sheet from a hot calender device is a critical issue. Furthermore, such composition lacks in hot tensile strength.